STRUCTURAL RELAXATION OF AMORPHOUS-SILICON DURING THERMAL AND CW LASER ANNEALING

Different amorphous silicon thin films were prepared by high energy io n bombardment of crystalline silicon (a-Si) and by magnetron sputterin g deposition (a-Si:H and a-Si1-xCx:H). All samples were laser annealed and a-Si sample was thermally annealed. Structural changes were monit ored by bandwidth and position of transverse optical (TO)-like vibrati onal band in Raman spectrum of amorphous silicon. They were compared w ith changes of broad background signal, recently interpreted as 'boson peak'. Correlation of structural and boson peak changes was explained by a fractal model. (C) 1998 Elsevier Science B.V. All rights reserve d.